Projection Printing

Projection printing, keep away from mask damage entirely. An image of the patterns on the mask is projected onto the resist-coated wafer, which are many centimetres away. In order to achieve high resolution, only a small portion of the mask is imaged. This small image field is scanned or stepped above the surface of the wafer. Projection printers that step the mask image over the wafer surface are known as step-and-repeat systems. Step-and-repeat projection printers are able of approximately 1-micron resolution.